Fix BTS attribute requests

* fix BTS numbers: use 0 to indicate given BTS and 0xFF to indicate all
  BTS' as it's explained in 3GPP TS 52.021 ยง9.3.
* only request attributes from supported (OsmoBTS) types

Change-Id: I8f43055c38000248033a8ff9ddaf0910d68d794b
Related: OS#2317
diff --git a/src/libbsc/bsc_init.c b/src/libbsc/bsc_init.c
index 64dcd15..6f80958 100644
--- a/src/libbsc/bsc_init.c
+++ b/src/libbsc/bsc_init.c
@@ -350,12 +350,12 @@
 			generate_cell_chan_list(ca, trx->bts);
 
 			/* Request generic BTS-level attributes */
-			abis_nm_get_attr(trx->bts, NM_OC_BTS, trx->bts->nr, trx->nr, 0xFF, bts_attr, sizeof(bts_attr));
+			abis_nm_get_attr(trx->bts, NM_OC_BTS, 0xFF, 0xFF, 0xFF, bts_attr, sizeof(bts_attr));
 
 			llist_for_each_entry(cur_trx, &trx->bts->trx_list, list) {
 				int i;
 				/* Request TRX-level attributes */
-				abis_nm_get_attr(cur_trx->bts, NM_OC_BASEB_TRANSC, cur_trx->bts->nr, cur_trx->nr, 0xFF,
+				abis_nm_get_attr(cur_trx->bts, NM_OC_BASEB_TRANSC, 0, cur_trx->nr, 0xFF,
 						 trx_attr, sizeof(trx_attr));
 				for (i = 0; i < ARRAY_SIZE(cur_trx->ts); i++)
 					generate_ma_for_ts(&cur_trx->ts[i]);